Coach lock safety catch



Mara 19, 1940. A, G, A PBELL 2,194,005

COACH LOCK SAFETY CATCH Filed May 23, 1938 2 Sheets-Sheet 1 findrew 6. CampfieZZ ATTORNEY5 March 19, 1940. CAMPBELL 2,194,005

COACH LOCK SAFETY CATCH Filed May 23, 1938 2 Sheets-Sheet 2 I N VENTOR.

ATTORNEYS Patented Mar. 19 1940 COACH LOCK FFlCE SAFETY oA'ron:

Andrew G. Campbell, Cleveland, hio, assignor .to'General Motors Corporation, Detroit, Mich.,.

a corporation of Delaware.

Application May 23, 1938 Serial No. 209,520

3 Claims.

I 1 Thisinvention relates to safety catches for automobile doors. The motor car of today is commonly provided with a safety catch for the latch bolt in the form of an automobile striker plate with two fixed humps or inclines over which the beveled head of the bolt has to climb before it reaches its final resting place. This arrangement works satisfactorily but it requires a considerable effort to close the door.

Itha's beenproposed recently to make the first hump or the safety catch in the form of a pivoted catch which is projected outwardly by a light spring and to make a gradual incline over which the bolt head climbs to surmount the second hump, This materially lessens the effort required to close the door. ,It is an old principle shown particularly in the several patents to Kaye, United States Patent No. 1,681,346, the British Patents 10,522 of 1893, 1,205 of 1908, 248,287 and the British Patent 388,500 to The Pressed Steel Company, etc.

It is the object of the present invention to provide a safety catch which is entirely incorporated in the lock unit. This eliminates a projecting catch on the body pillar which is liable to'catch clothing and it also eliminates all moving parts, springs, etc. from the striker and, I believe, makes a striker which is, in some respects, simpler and cheaper than the striker plate form of safety catch.

In the drawings:

- Fig. 1 is an elevation of a lock embodying one form of safety catch.

Fig. 2 is an elevation looking at the lock from the selvage plate side. i I

Fig. 3 is a section on the line 33 of Fig.1.

Fig. 4 is'a similar section showing the latch bolt catching on the safety latch.

Fig. 4A is an end elevation of the latch bolt head.

Fig. 5 is a detail perspective of the striker plate.

Figs. '6, 8 and 9 are similar views of another form of the invention, and

Fig. 7 is a section on the line 1-1 of Fig. 6.

Figs. 10, 11 and 12 are similar views of a third form of the invention.

Fig. 13 is a perspective detail of the striker for this third form.

The form of the lock is of no importance. So 50 I shall not describe the detail parts of this. The

lock shown happens to be a Ternstedt look now in very general use'and is described and claimed in the Andersen and Bowlus Patent No. 2,039,873. Suffice it to say here that l is the sliding bolt 55, which is normally projected by a relatively strong spring 2. In the bolt head is a sliding safety catch 3 having the beveled .end projected by spring 0.. This safety catch is secured in' the bolt head by simply drilling a hole in the head, put-g ting in the spring 0 and the sliding plunger. Pin 55 limits the projection of catch 3 with'respect to bolt l. The striker is provided with a' long gradual incline 5. A little morethan halfway up this incline, the striker plate is provided we slot 6' which forms a safety catch keeper or recess. I

When the latch bolt strikes the striker, it starts to climb a relatively gradual incline. The safety catch 3, being projected by a relatively light spring, is easily withdrawn and, as soon as this plungerpasses the beginning of thesafety catch slot, it shoots into this and insures the door catching in case the door is not closed with sufficient force to cause the main latch bolt to climb over the apex of the striker. I

The modification shown in Figs. 6-9 inclusive employs a safety catch which is unique in that it does not project beyond the head of the bolt When the bo1t is fully projected. The safety catch is designated 1. This is normally projected by the safety pin type of spring 8 which engages with a lug 9*on the plunger 1. This lug projects through slot I 0 in the bolthead. Pin limits the cutward'projection of the'plunger I by engaging against stop 5! at the end of slot 52 in the lock casing. Slot 53 allows latch head lit to be partially retracted without retracting plunger the latch bolt head and the safety catch strike the striker, both of them are retracted by reason of riding up the striker but, as soon as the-safety catch registers with the safety catch slot 6, the spring 8 causes the safety catch to spring into 7 this recess as shown in Fig. 9. The door is now insured of catching even though it is' not closed with 'suilicient effort to cause the latch bolt to climb the apex of the striker. The safety catch is retracted when the bolt'is retracted but the initial movement of retraction of the bolt does not retract the safety catch .until the end ll of the slot 53 picks up the lug 9. There is, however,

after this pickup, at sufiicient movement of the safety catch to move it back toward the selvage' plate so as to celar the wall of the recess 6 in passingbackward over the striker plate.

The form of safety catch shown in Figs. 10-12 inclusive works on identically the same principle as the second form justdescribed but here the safety catch is a separate member from the latch The mode of operation is as follows: When bolt head. The safety pin type of spring I! normally keeps it projected and the leg l3 on the end of the safety catch engages the stop 14 to prevent the spring [2 projecting clear out of the latch casing. When the latch bolt is first withdrawn, it has some movement before it withdraws the safety catch I5. Then the pin l6 picks up the leg I 3 and withdraws the catch.

What I claim is:

1. In a coach lock provided with a striker having a gradual incline and a shoulder at the apex behind which the latch bolt comes to-rest, the said striker provided with a slot forming a safety catch recess, the combination of a casing, a sliding latch bolt therein provided with a head, means for yieldingly projecting the same, a safety catch yieldingly projected from the latch casing and arranged to ride up the gradual incline and drop into the safety catch recess and means on the bolt for picking up the safety catch for retraction but only after a limited movement of the bolt has already been had.

2. In a coach lock provided with a striker having a gradual incline and a shoulder at the apex behind which the latch bolt comes to rest, the said striker provided with a slot forming a safety catch recess, the combination of a casing, a sliding latch bolt therein provided with a head, means for yieldingly projecting the same, and a safety catch latch yieldingly projected from the latch casing and arranged to ride up the gradual incline and drop into the safety catch recess and means on the sliding bolt for retracting the safety catch, the said safety catch being arranged to project no farther from the latch casing than the latch bolt head and being arranged to be picked up by the latch bolt head for retraction after the latch bolt head has made a limited movement back into the latch casing.

3. In a coach lock provided with a striker having a single gradual incline and a shoulder at the apex behind which the latch bolt comes to rest, the said striker provided with a slot forming a safety catch recess, the combination of a casing, a sliding latch bolt therein provided with a head, means for yieldingly projecting the same, a safety catch latch yieldingly projected from the latch casing and arranged to ride up the gradual incline and drop into the safety catch recess and means on the sliding bolt for retracting the safety catch, the said safety catch being in the form of a plunger reciprocating in an opening in the latch bolt head and the said catch arranged not to project beyond the latch bolt head when in its extreme position and arranged to be picked up by the latch bolt head only after the latch bolt head has retreated into the latch casing a given distance.

ANDREW G. CAMPBELL. 

